Friday fiction: Quality control

Stepping up into the train the fabric of her pencil skirt tightens across the full width of what is very nearly a perfectly-formed behind. Delphine feels the fabric tense and strain against her skin, still ultra-sensitive from yesterday's chastisement.
As the thought crosses her mind she feels a stitch break, then another and another. She hears it happen - a ripping noise that's like machinegun fire in miniature.
She darts a glance in both directions sure someone will have heard. But there's no-one that close and the busy station concourse is full of far bigger sounds.
“Bloody Nora,” she says under her breath. “That's tor it. Just can’t buy quality anywhere anymore.” Good lingerie is important to Delphine. She likes nice things, but it seems that manufacturers can't - or won't - cater for a girl with curves like hers.
She likes to wear something especially special for an important meeting like this one, so she’d chosen to put on something new that morning. Pale blue, so filmy you could read through them (should you care to) and decorated with teasing little bows.
Utterly charming, but perhaps not made for the stresses and strains that came with containing her bottom. Settling into a seat by the window she finds herself wondering what he will make of it; afterall, he is so very particular about standards. Turning up in ripped knickers is unlikely to go down well.